Cross-arm



GROSS ARM Filed Dc. 28, 1923 IN VE N TOR A. I? Has/51m! ATTORNEY Patented Sept. 13, 1927.

UNITED STATES PATENT OFFICE.

ROGER E. HOSFORD, OF MONTGLAIR, NEW JERSEY, ASSIGNOR TO AMERICAN TELE- PHONE AND TELEGRAPH CDMPANY, A CORPORATION OF NEW YORK.

GROSS-ARM.

Application filed December 28, 1923.

This invention relates to crossarms which are mounted on poles to carry telephone or telegraphs wires and the like.

The object of the invention is to reduce the amount of timber necessary to the construction of suitable crossarms, and to this end applicant provides a novel form of crossarm.

It has been the standard practice in line construction to equip the poles with crossarms consisting of a single main member of considerable thickness and to provide a series of round holes to receive the shanks of the insulator pins, the holes nearest the pole being known as the pole pin holes. In this standard practice, the actual strength of the crossarm must almost always be determined by the situation at these pole pin holes.

In applicants crossarm, two pieces of wood are employed, each having considerably less than half the thickness of the present standard crossarm, and the pole pins, as well as the other insulator pins, are secured to the crossarm in such a manner as to obviate the necessity of using pin holes. Thus, the original strength of each crossarm member is preserved, and, consequently, a far smaller total thickness of wood will suflice. Furthermore, standard thicknesses of lumber may be utilized.

It is proposed to describe in detail a preferred form of crossarm constructed according to applicants invention. This comprises two parallel main members, which may be considerably less than half as thick as the present standard crossarm. The insulator pins, which preferably have squared shanks, are external to the boundaries of the main crossarm members, that is, they are secured to the main members without being inserted into pin holes, or in anyway piercing any part of the main members. Thus, the main members retain their original Serial No. 683,236.

strength, and the reduced thickness is sufficient for all purposes.

The drawing covers the preferred form of the crossarm, with two insulator pins carrled thereon, representative of any suitable number of pins. The crossarm is shown in top plan and side elevation in Figures 1 and 2, with the two insulator pins included. Figure 3 shows a cross-section view, taken on the line 33 of Fig. 2 in the direction indicated by the arrows. Like numerals of reference in the several figures of the drawing designate corresponding parts of the device.

With reference to the details of the drawing, the main crossarm members 1 and 2 are narrow pieces of wood fixed in separated relation, but lie close together, being separat-ed by only a narrow space. Any suitable attaching means may be used. The insulator pins 4 and 5 have shanks which are deeply grooved, and the prongs 7 and 8 of the shank straddle the main member 1. Any suitable means may be employed for securing the insulator pin to the main members- It is to be understood that the above detailed description merely covers a preferred specific embodiment of applicants invention, serving the purpose of clear illustration. It does not limit the scope of the invention, which is to be determined by the appended claim.

What is claimed is:

A crossarm comprising two parallel main members fixed in separated relation to each other, and a plurality of insulator pins secured to said main members, said insulator pins being deeply grooved from the bottoms thereof to fit over one of said main members.

In testimony whereof, I have signed my name to this specification this 27th day of December 1928.

ROGER F. HOSFORD. 

